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1.
Int J Cancer ; 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33783821

RESUMO

Biological evidence suggests that vitamin D has numerous anticancer functions, but the associations between vitamin D status and colorectal cancer (CRC) risk and survival remain inconclusive. Based on UK Biobank, we prospectively evaluated the associations of season-standardized 25-hydroxyvitamin D (25(OH)D) concentrations with CRC risk among 360 061 participants, and with survival among 2509 CRC cases. We observed an inverse linear relationship between 25(OH)D concentrations and CRC risk (P for linearity = .01; HR per 1-SD increment, 0.95; 95% CI, 0.91-0.99). Compared to the lowest quartile of 25(OH)D, the highest quartile was associated with a 13% (HR, 0.87; 95% CI, 0.77-0.98) lower risk of CRC. For CRC survival, compared to those in the lowest quartile of 25(OH)D, cases in the highest quartile had a 20% (HR, 0.80; 95% CI, 0.65-0.99) lower risk for overall death. Our findings indicate that higher concentrations of serum 25(OH)D are associated with lower incidence and improved survival of CRC, suggesting a role of vitamin D in the pathogenesis of CRC.

2.
Eur J Endocrinol ; 184(5): 723-732, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33690154

RESUMO

Objective: Testosterone is a critical determinant of health in both genders. However, the relationship between circulating levels of testosterone and mortality remains undetermined. Methods: We examined the associations of serum total testosterone (TT) and free testosterone (FT) with all-cause and cause-specific mortality in 154 965 men and 93 314 postmenopausal women from UK Biobank. Cox regression models were used to calculate the hazard ratios (HR) and 95% CIs. Given multiple testing, P < 0.005 was considered statistically significant. Results: Over a median follow-up of 8.9 (inter-quartile range: 8.3-9.5) years, we documented 5754 deaths in men, including 1243 (21.6%) from CVD and 2987 (51.9%) from cancer. In postmenopausal women, 2435 deaths occurred, including 346 (14.2%) from CVD and 1583 (65.0%) from cancer. TT and FT concentrations were inversely associated with all-cause mortality in men, with the multivariable HR of 0.82 (95% CI: 0.75-0.91) and 0.80 (95% CI: 0.73-0.87) for the highest (Q5) vs the lowest quintile (Q1), respectively. In postmenopausal women, TT concentrations showed a positive association with all-cause mortality (HR for Q5 vs Q1 = 1.20, 95% CI: 1.06-1.37). Furthermore, higher TT and FT concentrations were associated with a lower risk of cancer mortality in men (both P for trend = 0.001), whereas TT concentrations were suggestively associated with a higher risk of cancer mortality in postmenopausal women (P for trend = 0.03). Conclusions: Our findings suggest that high levels of circulating testosterone may be beneficial for all-cause and cancer mortality in men but detrimental in postmenopausal women.

3.
Eur J Epidemiol ; 36(3): 311-318, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33420872

RESUMO

Coronavirus disease 2019 (COVID-19) deteriorates suddenly primarily due to excessive inflammatory injury, and insulin-like growth factor-1 (IGF-1) is implicated in endocrine control of the immune system. However, the effect of IGF-1 levels on COVID-19 prognosis remains unknown. Using UK Biobank resource, we investigated the association between circulating IGF-1 concentrations and mortality risk (available death data updated on 07 Sep 2020) among COVID-19 patients who had pre-diagnostic serum IGF-1 measurements at baseline (2006-2010). Unconditional logistic regression was performed to estimate the odds ratio (OR) and 95% confidence intervals (CIs) of mortality. Among 1670 COVID-19 patients, 415 deaths occurred due to COVID-19. Compared to the lowest quartile of IGF-1 concentrations, the highest quartile was associated with a 41% lower risk of mortality (OR = 0.59, 95% CI 0.41-0.86, P-trend = 0.01). In the continuous model, per 1-standard deviation increment in log-transformed IGF-1 was associated with a 15% reduction in the risk (intraclass correlation coefficients corrected OR = 0.85, 95% CI 0.73-0.99). The association was largely consistent in the various stratified and sensitivity analyses. In conclusion, our data suggest that higher IGF-1 concentrations are associated with a lower risk of COVID-19 mortality. Further studies are required to determine whether and how targeting IGF-1 pathway might improve COVID-19 prognosis.

4.
Gene ; 767: 145287, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-33181258

RESUMO

BACKGROUND: Chronic respiratory diseases have become a non-negligible cause of death globally. Although smoking and environmental exposures are primary risk factors for chronic respiratory diseases, genetic factors also play an important role in determining individual's susceptibility to diseases. Here we performed integrated gene-based and pathway analyses to systematically illuminate the heritable characteristics of chronic respiratory diseases. METHODS: UK (United Kingdom) Biobank is a very large, population-based prospective study with over 500,000 participants, established to allow detailed investigations of the genetic and nongenetic determinants of the diseases. Utilizing the GWAS-summarized data downloaded from UK Biobank, we conducted gene-based analysis to obtain associations of susceptibility genes with asthma, chronic obstructive pulmonary disease(COPD) and pneumonia using FUSION and MAGMA software. Across the identified susceptibility regions, functional annotation integrating multiple functional data sources was performed to explore potential regulatory mechanisms with INQUISIT algorithm. To further detect the biological process involved in the development of chronic respiratory diseases, we undertook pathway enrichment analysis with the R package (clusterProfiler). RESULTS: A total of 195 susceptibility genes were identified significantly associated with chronic respiratory diseases (Pbonferroni < 0.05), and 24/195 located out of known susceptibility regions (e.g. WDPCP in 2p15). Within the identified susceptibility regions, functional annotation revealed an aggregation of credible variants in promoter-like and enhancer-like histone modification regions and such regulatory mechanisms were specific to lung tissues. Furthermore, 110 genes with INQUISIT score ≥1 may influence diseases susceptibility through exerting effects on coding sequences, proximal promoter and distal enhancer regulations. Pathway enrichment results showed that these genes were enriched in immune-related processes and nicotinic acetylcholine receptors pathways. CONCLUSIONS: This study implemented an integrated gene-based and pathway strategy to explore the underlying biological mechanisms and our findings may serve as promising targets for future clinical treatments of chronic respiratory diseases.


Assuntos
Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla/métodos , Transtornos Respiratórios/genética , Asma/genética , Bancos de Espécimes Biológicos , Doença Crônica/epidemiologia , Bases de Dados Genéticas , Feminino , Humanos , Pulmão/fisiopatologia , Masculino , Polimorfismo de Nucleotídeo Único/genética , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/genética , Fumar/genética , Reino Unido
5.
J Clin Endocrinol Metab ; 105(10)2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32620963

RESUMO

CONTEXT: Although an inverse association between vitamin D status and mortality has been reported in observational studies, the precise association shape and optimal vitamin D status remain undetermined. OBJECTIVE: To investigate the association between vitamin D status and risk of all-cause and cause-specific mortality and estimate optimal serum 25-hydroxyvitamin D [25(OH)D] concentrations. DESIGN: Prospective cohort study. SETTING: UK Biobank. PARTICIPANTS: 365 530 participants who had serum 25(OH)D measurements and no history of cardiovascular disease (CVD), cancer, or diabetes at baseline (2006-2010). MAIN OUTCOME MEASURES: All-cause and cause-specific mortality. RESULTS: During a median follow-up of 8.9 (interquartile range: 8.3-9.5) years, 10 175 deaths occurred, including 1841 (18.1%) due to CVD and 5737 (56.4%) due to cancer. The multivariate analyses revealed nonlinear inverse associations, with a decrease in mortality risk appearing to level off at 60 nmol/L of 25(OH)D for all-cause and CVD deaths and at 45 nmol/L for cancer deaths. Compared to participants with 25(OH)D concentrations below the cutoffs, those with higher concentrations had a 17% lower risk for all-cause mortality (hazard ratio [HR]: 0.83, 95% confidence interval [CI]: 0.79-0.86), 23% lower risk for CVD mortality (HR: 0.77, 95% CI: 0.68-0.86), and 11% lower risk for cancer mortality (HR: 0.89, 95% CI: 0.84-0.95). CONCLUSIONS: Higher 25(OH)D concentrations are nonlinearly associated with lower risk of all-cause, CVD, and cancer mortality. The thresholds of 45 to 60 nmol/L might represent an intervention target to reduce the overall risk of premature death, which needs further confirmation in large clinical trials.

6.
Mol Carcinog ; 58(7): 1303-1313, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31026380

RESUMO

Identification of long noncoding RNA (lncRNA) expression quantitative trait loci (lncR-eQTL) that associated with lung cancer can provide insights into regulatory mechanisms of lncRNA, and help reveal the role of lncRNA in lung cancer. A two-stage case-control design was implemented in this study. We first selected the lncRNAs that differently expressed based on the Cancer Genome Atlas (TCGA) project (75 normal and 708 tumor tissues) and identified eQTLs for selected lncRNAs based on data of 278 normal lung tissues from the the genotype-tissue expression database. Then we selected lncR-eQTLs that associated with lung cancer based on two lung cancer GWAS datasets (7127 cases and 6818 controls). Promising lncR-eQTLs were further replicated in an additional population (1056 cases and 1053 controls). Functional annotations of the identified lncR-eQTLs and related lncRNAs were finally performed by using multiple public databases. Our eQTL analysis finally detected three lncRNA-eQTLs, rs793544 in 3q13.12 (odds ratio [OR] = 1.15; confidence interval [CI]:1.09-1.22; P = 2.30 × 10-6 ), rs7234707 in 18p11.31 (OR = 1.1; CI:1.05-1.15; P = 9.01 × 10-5 ) and rs1600249 in 8p23.1 (OR = 1.1; CI:1.05-1.16; P = 1.27 × 10-4 ), that were consistently associated with the risk of lung cancer. These findings indicate that lncR-eQTLs may serve as novel susceptibility markers for lung cancer.


Assuntos
Estudos de Associação Genética , Predisposição Genética para Doença/genética , Neoplasias Pulmonares/genética , RNA Longo não Codificante/genética , Grupo com Ancestrais do Continente Asiático/genética , Estudos de Casos e Controles , Humanos , Pulmão/patologia , Neoplasias Pulmonares/patologia , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genética
7.
Front Oncol ; 9: 1492, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32010612

RESUMO

Genome-wide association studies (GWASs) have identified hundreds of single nucleotide polymorphisms (SNPs) associated with cancer risk, several of which have shown pleiotropic effects across cancers. Therefore, we performed a systematic cross-cancer pleiotropic analysis to detect the effects of GWAS-identified variants from non-lung cancers on lung cancer risk in 12,843 cases and 12,639 controls from four lung cancer GWASs. The overall association between variants in each cancer and risk of lung cancer was explored using sequential kernel association test (SKAT) analysis. For single variant analysis, we combined the result of specific study using fixed-effect meta-analysis. We performed functional exploration of significant associations based on features from public databases. To further detect the biological mechanism underlying identified observations, pathway enrichment analysis were conducted with R package "clusterProfiler." SNP-set analysis revealed the overall associations between variants of 8 cancer types and lung cancer risk. Single variant analysis identified 6 novel SNPs related to lung cancer risk after multiple correction (P fdr < 0.10), including rs1707302 (1p34.1, OR = 0.93, 95% CI: 0.90-0.97, P = 7.60 × 10-4), rs2516448 (6p21.33, OR = 1.07, 95% CI: 1.03-1.11, P = 1.00 × 10-3), rs3869062 (6p22.1, OR = 0.91, 95% CI: 0.86-0.96, P = 7.10 × 10-4), rs174549 (11q12.2, OR = 0.90, 95% CI: 0.87-0.94, P = 1.00 × 10-7), rs7193541 (16q23.1, OR = 0.93, 95% CI: 0.90-0.96, P = 1.20 × 10-4), and rs8064454 (17q12, OR = 1.07, 95% CI: 1.03-1.11, P = 4.30 × 10-4). The eQTL analysis and functional annotation suggested that these variants might modify lung cancer susceptibility through regulating the expression of related genes. Pathway enrichment analysis showed that genes modulated by these variants play important roles in cancer carcinogenesis. Our findings demonstrate the pleiotropic associations between non-lung cancer susceptibility loci and lung cancer risk, providing important insights into the shared mechanisms of carcinogenesis across cancers.

8.
Toxicol Lett ; 273: 10-19, 2017 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-28302560

RESUMO

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is a widespread environmental pollutant that could induce serious toxic effects in both humans and rodents. Some studies suggested that TCDD exposure may facilitate the activation of hepatic stellate cells (HSCs) and liver injury. However, the underlying molecular mechanism by which environmental pollutants promote liver injury remains poorly understood. In the present study, we established an animal model of TCDD exposure by intraperitoneal injection of TCDD in male C57BL/6J mice. As revealed by Sirius red staining and hematoxylin-eosin (H&E) staining evaluation, we found that TCDD-exposed mice showed extensive disruption of liver architecture, including hepatocellular necrosis, inflammatory cell infiltration, and fibrosis. Furthermore, we showed that TCDD up-regulated the expression and secretion of the pro-inflammatory cytokines tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) in a dose-dependent manner in cultured HSCs. The effects of TCDD on cytokine secretion were very likely mediated by protein kinase B/Akt and Nuclear Factor kappa B (NF-κB) pathways, as indicated by the fact that TCDD markedly increased Akt phosphorylation and nuclear translocation of NF-κB p65 in HSCs. Furthermore, LY294002, an Akt inhibitor, significantly attenuated TCDD-triggered HSC activation through blocking Akt phosphorylation and NF-κB activation. These results indicate that HSCs are susceptible to the cytotoxic effects of TCDD and chronic TCDD exposure may contribute to liver fibrosis by activating HSC Akt and NF-κB signaling pathways.


Assuntos
Poluentes Ambientais/toxicidade , Células Estreladas do Fígado/efeitos dos fármacos , Cirrose Hepática Experimental/induzido quimicamente , NF-kappa B/metabolismo , Dibenzodioxinas Policloradas/toxicidade , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Células Cultivadas , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Interleucina-6/metabolismo , Cirrose Hepática Experimental/metabolismo , Cirrose Hepática Experimental/patologia , Masculino , Camundongos Endogâmicos C57BL , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo
9.
Sci Rep ; 6: 33739, 2016 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-27653140

RESUMO

Both chronic calorie restriction (CCR) and intermittent calorie restriction (ICR) have shown anticancer effects. However, the direct evidence comparing ICR to CCR with respect to cancer prevention is controversial and inconclusive. PubMed and Web of Science were searched on November 25, 2015. The relative risk (RR) [95% confidence interval (CI)] was calculated for tumor incidence, and the standardised mean difference (95% CI) was computed for levels of serum insulin-like growth factor-1 (IGF-1), leptin, and adiponectin using a random-effects meta-analysis. Sixteen studies were identified, including 11 using genetically engineered mouse models (908 animals with 38-76 weeks of follow-up) and 5 using chemically induced rat models (379 animals with 7-18 weeks of follow-up). Compared to CCR, ICR decreased tumor incidence in genetically engineered models (RR = 0.57; 95% CI: 0.37, 0.88) but increased the risk in chemically induced models (RR = 1.53, 95% CI: 1.13, 2.06). It appears that ICR decreases IGF-1 and leptin and increases adiponectin in genetically engineered models. Thus, the evidence suggests that ICR exerts greater anticancer effect in genetically engineered mouse models but weaker cancer prevention benefit in chemically induced rat models as compared to CCR. Further studies are warranted to confirm our findings and elucidate the mechanisms responsible for these effects.

10.
Neurotoxicology ; 44: 149-59, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24932542

RESUMO

Studies have shown that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induces apoptotic cell death in neuronal cells. However, whether this is the result of endoplasmic reticulum (ER) stress-mediated apoptosis remains unknown. In this study, we determined whether ER stress plays a role in the TCDD-induced apoptosis of pheochromocytoma (PC12) cells and primary neurons. PC12 cells were exposed to different TCDD concentrations (1, 10, 100, 200, or 500nM) for varying lengths of time (1, 3, 6, 12, or 24h). TCDD concentrations much higher than 10nM (100, 200, or 500nM) markedly increased glucose-regulated protein (GRP78) and C/EBP homologous protein (CHOP) levels, which are hallmarks of ER stress. We also evaluated the effects of TCDD on ER morphology in PC12 cells and primary neurons that were treated with different TCDD concentrations (1, 10, 50, or 200nM) for 24h. Ultrastructural ER alterations were observed with transmission electron microscopy in PC12 cells and primary neurons treated with high concentrations of TCDD. Furthermore, TCDD-induced ER stress significantly promoted the activation of the PKR-like ER kinase (PERK), a sensor for the unfolded protein response (UPR), and its downstream target eukaryotic translation initiation factor 2 α (eIF2α); in contrast, TCDD did not appear to affect inositol-requiring enzyme 1 (IRE1) and activating transcription factor 6 (ATF6), two other UPR sensors. Importantly, TCDD significantly inhibited eIF2α phosphorylation and triggered apoptosis in PC12 cells after 6-24h of treatment. Salubrinal, which activates the PERK-eIF2α pathway, significantly enhanced eIF2α phosphorylation in PC12 cells and attenuated the TCDD-induced cell death. In contrast, knocking down eIF2α using small interfering RNA markedly enhanced TCDD-induced cell death. Together, these results indicate that the PERK-eIF2α pathway plays an important role in TCDD-induced ER stress and apoptosis in PC12 cells.


Assuntos
Apoptose/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Dibenzodioxinas Policloradas/toxicidade , eIF-2 Quinase/metabolismo , Animais , Cinamatos/farmacologia , Retículo Endoplasmático/enzimologia , Retículo Endoplasmático/ultraestrutura , Células PC12 , Ratos , Transdução de Sinais , Tioureia/análogos & derivados , Tioureia/farmacologia , Resposta a Proteínas não Dobradas
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